Commonly refers to terrorist factions. There are countless indications to determine whether or not someone is radical right-wing, but the most dominant indicator is that the person, or group, believes greatly in war and fulfilling objectives through means of terrorism. There is possible lack of belief in human life involved as well.

"Whoever says Bush is radical right-wing clearly doesn't know jackshit. Bush is just right-wing. You can't just call him radical right-wing just because we went to war. But then again what do I know; I try to veer away from politics."
-me